This invention relates to a method for translating rotary motion to non-rotary motion, such as linear motion, and to apparatus for operating in accordance with the method. The invention is particularly well suited to applications in the machine tool art wherein a workpiece is carried on a rotating member for feeding past a tool element. In particular, the method and apparatus of the present invention are believed to provide great benefits when used with surface grinding machines, profile grinding machines, milling machines and the like to obtain a "through-feed" system of operation.
With respect to translating circular or rotary movement to non-circular or linear movement, it is known to use a fixed track or guideway for receiving and guiding a moving member. However, with many types of prior art systems, the complexity of the structure and of the range of motions of various members comprising the structure, make it very difficult to provide an apparatus with a high degree of dynamic rigidity. Consequently, many of these prior art machines operate with more than the desired amount of vibration, more than the desired amount of deviation from the intended feed path, and more than the desired probability of failure.
With machine tools, it is especially desired to provide methods and structures which maintain the workpiece and the tool, when in contact, with a minimum of structural flexing or vibration so that accurate tooling operations can be performed.
It would be especially desirable to provide a method and an apparatus for utilizing common rotary motion and for translating that rotary motion to a non-rotary or linear motion for feeding a workpiece against a tool with a high degree of dynamic rigidity and with no, or insignificant, vibration.